Theoretical combustion temperature of the coal, as well as the combustion temperatures of three different calorific value coal in the cement kiln under the given conditions were calculated. The results show that theoretical combustion temperature decreases with the decreasing heat value of the coal, and with the same calorific value, the higher the moisture content of the coal, the lower the theoretical combustion temperature. In the cement rotary kiln, the maximum flue gas temperature is relatively low, and the temperature of the flue gas out of the kiln and the unit heat consumption of clinker is relatively high when the calorific value of the coal is relatively low in the condition of the same combustion rate.

The causes of oil leak and powder into of the roller used in roller mill were analyzed. Then the roller was optimized and improved from the following aspects: skeleton oil seal, air sealing, and the structure of the rollers, to ensure the stable operation of the roller mill. Meanwhile, the routine maintenance workload of the roller mill has been reduced. It provides a nice reference for design and maintenance of the various types of roller mill.

The slag and cement were respectively grinded using a TRMKS43.4 roller mill in Wuhan Yangluo cement co., Ltd. The design specifications of the two materials have been reached through the rational process design and operation optimization. Additionally, continuous conversion of two grindings has been achieved. The clinker and slag were grinded to the powders with different surface area, then into the Semi-finished library. According to different proportions, cement with different strength levels can be obtained after being stirring by the mixer. After adjustment, cement with excellent performance can be obtained, and the continuous conversion of dual material roll mill is also successfully realized.